OpenZFS on OS X

The installer release of OpenZFS on OS X is ready for use by people who are comfortable with administering ZFS from the Terminal or who are willing to learn to do so. It's compatible with OS X 10.8 through OS X 10.11 (Mountain Lion, Mavericks, Yosemite and El Capitan).

FreeBSD®

A full general purpose operating system with several specialized distributions.

Debian® GNU/kFreeBSD

Debian® GNU/kFreeBSD is a general purpose GNU distribution for amd64/i386 that uses the FreeBSD kernel, which provides an OpenZFS implementation.

An official Debian release, still using GNU libc and with ninety percent of the same software packages available.

The wheezy stable release:

can dual-boot 9.0 (default) or 8.3 kernels of FreeBSD

uses pool version 28 (deduplication, raidz3, removable log devices)

lacks support for ashift=, and important development tools like DTrace

installer supports creation of pools, installing to them, and booting directly from them with GRUB2.

The testing release will be updated with new FreeBSD kernel releases, gaining many OpenZFS enhancements, including support for lz4 compression.

PC-BSD®

illumos

The illumos codebase is the foundation for various distributions – comparable to the relationship between the Linux kernel and Linux distributions.
The codebase originated as a fork from the last release of OpenSolaris.

OpenIndiana

SmartOS™

SmartOS is a specialised type 1 hypervisor platform that is lean enough to run entirely in memory and powerful enough to run as much as you want to throw at it. Provisioning is blindingly fast, thanks to zones and ZFS file system creation. SmartOS is a fundamental component of the Joyent® SmartDataCenter™ (SDC) product.

Gentoo

Gentoo can be automatically optimized and customized for just about any application or need. Extreme configurability, performance and a top-notch user and developer community are all hallmarks of the Gentoo experience.

Derivatives include:

Funtoo Linux, which features native UTF-8 support enabled by default, a git-based, distributed Portage Tree and funtoo overlay, an enhanced Portage with more compact mini-manifest tree, automated imports of new Gentoo changes every 12 hours, GPT/GUID boot support and streamlined boot configuration, enhanced network configuration, up-to-date stable and current Funtoo stages, all built using Funtoo's Metro build tool